This invention relates to sprinkler arrangements and more particularly to fast response residential sprinkler arrangements.
The National Fire Protection Association standards NFPA 13D and 13R for residential sprinklers specify minimum flow rates of 9 gallons per minute at a pressure of 9 psi for single sprinklers having a maximum spacing of 6 feet from a wall and 10 gallons per minute at a pressure of 11.1 psi for single sprinklers having a maximum distance of 7 feet or 8 feet from a wall. For two or more sprinklers in the same room having 12, 14 or 16 foot spacings, the minimum required flow rate is 8 gallons per minute at a pressure of 7.1 psi. In order to provide the necessary protection, the distribution of water along the adjacent walls and over the floor area beneath the sprinklers should be substantially uniform.
Various sprinkler arrangements and deflector designs have been proposed heretofore to provide desired water flow rate distribution patterns. For example, the Bosio et al. U.S. Pat. No. 5,687,914 discloses a sprinkler arrangement having a deflector supported from a pair of frame arms which has enlarged tines in the plane of the frame arms with their inner ends bent away from the frame arms and their outer ends inclined slightly toward the frame arms. The Grinnell Model F680 sprinkler has a planar deflector with keyhole-shaped slots distributed around the periphery with the circular part of the keyhole for slots in the plane of the frame arms having a diameter smaller than that of the other slots. Those arrangements, however, do not provide the desired water distribution uniformity for flow rates and pressures of the type mentioned above for residential sprinklers.